<!DOCTYPE HTML>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>无标题文档</title>
</head>
<body>
<script>
var str = '';
for (var i=0; i<3; i++) {
	for (var j=0; j<12; j++) {
		str += '<div style="top: '+ i*55 +'px; left:' + j*55 + 'px; position:absolute; width:50px; height:50px; background:red;"></div>';
	}
}
document.body.innerHTML = str;

</script>

</body>
</html>
